How do I schedule a command to run after a delay in Vim?

Explanation

Vim's timer_start() function lets you schedule code to run after a specified delay in milliseconds. This enables deferred execution, polling, periodic updates, and other asynchronous patterns without blocking the editor.

How it works

• timer_start({ms}, {callback}) — runs callback after ms milliseconds
• The callback receives the timer ID as its argument
• Returns a timer ID for later cancellation
• timer_stop({id}) — cancels a scheduled timer

Example

" Run once after 2 seconds
:call timer_start(2000, {-> execute('echom "Hello!"')})

" Repeat every second (5 times)
:call timer_start(1000, {t -> execute('echom reltime()[0]')}, {'repeat': 5})

" Cancel a timer
:let tid = timer_start(5000, {-> execute('echo "late"')})
:call timer_stop(tid)

Tips

• Use {'repeat': -1} for an indefinitely repeating timer
• timer_info() lists all active timers
• Timers run when Vim is idle — they won't interrupt typing
• Useful for auto-save: timer_start(60000, {-> execute('silent! wall')}, {'repeat': -1})